Eyes that Perceive Reality is pretty good on some fights but Momiji does it better, since Satori possesses... nothing else to give her durability except a nice max hp count. Although if you're already using Satori it's something to keep in mind on gimmick fights, yeah.
I can see where you're going as elementalist, but it doesn't really sound like it'd pay off enough to be worth the effort, unfortunately. Trauma's damage isn't anything special unless you're using a super low delay move and Satori would require an awful lot of healing attention- nor does elementalist's buffs do very much or pack nearly a low enough delay to make it worthwhile.
If you want to make it work you need to use it with, at minimum, something like Marisa or Chen's self-buffs (88% and 95% delay), but they're both really fragile, so Reisen ( the godly 98%) is the only really good option. She can self-heal using said high-speed buffs if you sub enchanter, which is a good idea for damage burst style, but obviously it blows through her mp like mad and requires you to use fast swappers (tank-built awakened kogasa? or orin) to shuffle her around for Small Mp Recovery. HP build Satori certainly has potential, but she still doesn't really want to stay out longer than she needs to.
(Although it's kind of hilarious to imagine dragon god satori using patriot's elixir to buff up the front row, it's probably a hilarious waste of the class)
Mmm, Orin or Kogasa using their fast-swap skill to throw Satori around the frontline does sound effective. Build Reisen and Kogasa as tanks, Kogasa's got hp regen, sub Kogasa monk or healer for passive heal/buff addition, with 9300 atb swaps Satori can keep her mp flowing for elixirs for quite awhile... with about 68 max mp she wouldn't run out, if you also learn monk's ATB reduction and Kogasa has a bit more speed than her. Kogasa's passive heal plus subclass heal on 9300 atb turns will keep the front sort of healthy, the only problem is you're using 3 slots up. The 4th would just need to be like... Awakened Reimu or Minoriko to keep everyone alive.
edit:Oh wait, it's 9100 atb swaps. So 9190 if you're really minmaxing it with Monk. That's 4 casts of patriot's, could make it more like 3.5 with speed difference. 68 max MP on Satori would still last a reallllly long time, long enough. When it's time to stop, Kogasa can fastswap her and Reisen both out immediately for other members. Okay, how strong is Kogasa's regen in "event" battles with no terror up, that's what I'd curious about now.
For reference Satori should have 65 mp at lv440 with double mp boost and 10 mp gems, which should be a trivially easy amount of investment as MP gems are one of the most common ones. Her equips would be mostly for hp, but you could give her the mp using equips to never need to stop if you really wanted. That'd mostly be relevant if you wanted enough mp to spam Spiriting Away a lot too.
SO REGALSTAR. Could you grab Renko and Awakened Kogasa and run into the 2f FOE or something? Cast Charge n' see how much % Kogasa heals on her turn? o: I may have a full unlock save but it's not got awakened characters on it. Christ, now I'm imagining her and Satori both subbed healer. Front row recovers 20% max hp every ~800 atb ticks plus Kogasa's passive. It's so dumb. It's so good